Chapter 13. Abrasion, Finishing, Polishing, and Cleaning

Chapter 13. Abrasion, Finishing, Polishing, and

Cleaning

1. what is the goal of finishing and polishing restorations?:

is to remove excess material (flash), smooth roughened surfaces

and produce esthetically pleasing appearances with minimum

trauma to hard and soft tissues

2. why do we polish?: to get smooth margins, so the plaque

doesn't adhere and it reduces the risk of caries

3. what 3 things is the rate of abrasion determined by?: 1.

size, irregularity and hardness of the particles

2. number of particles contacting the surface

3. the pressure and speed with which particles are applied

4. the effect of abrasion is directly related to the properties of the

abrasive and the material it is abrading (true or false): true

5. hardness is the ability of material to resist abrasion (true or

false): true

, 6. what does the size, irregularity and hardness of the particle

size determine?: determines the depth of the scratches and the

amount of material being removed

(ex: pumice is not recommended for mild stain)

7. according to the moh hardness scale, what is the hardest

material?: diamond

8. according to moh hardness scale, what is the least hardest

material?: gold

9. what are some examples of abrasives?: -carbide finishing bur

-silicon carbide

-aluminum oxide

-sand/quartz

-pumice

10. carbide finishing bur: the more flutes the finer the finish (primarily

used for finishing)

11. silicon carbide: -coated disks

-rotary devices

-used in finishing procedures